This is a good point, but I will add, from close discussions with Dreyfus, his position was that it's impossible because it's fundamentally impossible, not because it's intractable. (see my other comment for more)
Interesting to learn about Dreyfus, I was aware of this line of thought from Francois Chollet's article. He is the creator of Keras and some pretty advanced research papers in the nature of intelligence.
He states that the environment and embodiment are crucial for the development of intelligence. Even for humans, 'our environment puts a hard limit on our individual intelligence'.
The implausibility of intelligence explosion (2017)
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In essence we need simulators on par with reality to train human-like intelligence. BTW, take a look at ThreeDWorld, just came out: 'A High-Fidelity, Multi-Modal Platform for Interactive Physical Simulation'. We're getting closer, and AI scientists are aware of the environment problem.
I have been interested in this debate for perhaps a decade now, and to me one of the most important things to get clear is whether skeptics are just claiming X is really hard, or whether they are claiming it's impossible as a matter of principle, which are two very different things. I think this discussion is about the latter rather than the former, but that many people talk about the former as if it's relevant to the latter.
